Um, Ike is horrifyingly BIG as it is, and the Gulf of Mexico is warm, meaning it's only going to get bigger and stronger until it gets right to the beach, and by then, it's too late to run. I'm not going to tell you what to do, but I will say that this thing is Katrina-esque but to a larger scale; if I were you, I'd recommend getting the hell out of Houston. I know some stuff about tropical systems (I study them as a hobby), and I will say that this thing is going to be beastly, whether or not it strengthens any more than it already has.
I'm watching the Weather Channel as I type this. No matter what's going to happen direction-wise, Houston WILL be impacted. If it goes to the left of Houston, the right side of the storm, which typically has the stronger quadrant of a tropical system, the wind and storm surge will be nasty. If it goes to the right, you'll be spared a bit.
If the eyewall goes over… Good luck. You're really going to need it.
I really think it's in YOUR best interests to evacuate. You have about a day. Gas up (use a credit card if you have to; forget the prices for now, your life is far more important), and get out of Texas. The highways are contraflowing, so you'll be able to get out quicker.
Again, I'm not telling you what to do, but I will say that it's not the smartest move to be gung-ho and ride the storm out. This thing is not going to be pretty.
Good luck, Kaze.